In the railway system, a system has been established wherein an interlocking device is conventionally used as a core of the signaling system so that it links and connects to a track circuit for detecting the presence of a train on the track, a point for switching railway tracks, and a signal device for transmitting permission for a train to proceed or not proceed along a track and does not allow a train to enter a track if there is danger of a collision or derailment.
Recently, as disclosed in Japanese Patent publication No. 7-41840, a method has been developed wherein a central apparatus wirelessly detects a train's location from an on-board device, and based on that train's location, the central apparatus links and controls a point and an on-board signal device.